of the Oil Beetle, Meloé, and of the Strepsiptera. 333 
Mr. Pickering argued, at that early period of our knowledge of the habits of 
Strepsiptera, incontestably proved that the parasite is admitted into the cell of 
the young bee before the cell is closed by its parent,—a view which has since 
been completely verified by the observations of Dr. Siebold. Two other spe- 
cimens of Stylops in Mr. Pickering's bee appear to have been females; so that 
both male and female Stylops have been found in the same insect. Some 
months after this, M. Van Heyden, of Frankfort, stated at the Congress of 
German Naturalists, held at Bonn in September 1835, that he had met with 
three species of Xenos (previously shown by him to the Rev. F. W. Hope*), 
X. Rossii, in Polistes gallica, and two others, one, much smaller than X. Rossii, 
in a species of Odynerus; and that he had found the body of the former some- 
times filled with minute living hexapods, which he also regarded as para- 
sites, and which resembled Acari, but which had the abdomen articulated. 
Further, Mr. Pickering in the following April (1836) obtained similar hexa- 
pods from Stylopst. Mr. Westwood, who had been directed by Van Heyden 
himself to the fact of the occurrence of these little objects in Xenos, and who 
had received from Mr. Pickering some specimens of these acariform bodies 
obtained from Stylops, and preserved in spirit, afterwards, in the month of June 
1836, found similar specimens on a stylopized bee, Andrena Gwynana, Kirb., 
in his own possession. These he also described in the Transactions of the 
Entomological Society as the parasites of Stylopst ; but questioned, in a note 
to his paper, whether these supposed parasites might not be the young of Sty- 
lops, and the supposed pupze, seen by Rossi, Kirby, Peck, and all subsequent 
observers, partially projecting from beneath the margin of the abdominal seg- 
ments of the stylopized insects, be the females ?, as, up to that time, and even 
to a still more recent period, the female Stylops remained unknown. Mr. 
Westwood added, however, * that he should be very fearful of asserting this as 
the fact." Yet such has since been shown by Dr. Siebold to be the truth. 
2e distinguished naturalist, in 1839 §, not only found similar hexapods on 
* Trans. Entom. Soc. Lond. vol. i. part 2. (Proceedings, xxxix.) 
T See Mr. Westwood's on the Parasit Stylops, T: 1 ii 
i paper e Parasites of Stylops, Trans. Ent. Soc. vol. u. part 3. p. 184, 
t Loc. cit. 
$ Ueber Xenos sphecidarum und dessen Schmarotzer, in Beitri 
, N: , i 1 
be Hur pie ge zur Naturgeschichte der Wirbel- 
3x 
